This study was performed to analyze the impact of transradial intervention (TRI), performed by long (25-cm) hydrophilic-coated radial introducer sheath (HRS), on radial artery (RA). Both acute damages and chronic intimal modifications, occurring in RA, were assessed using frequency domain-optical coherence tomography (FD-OCT). FD-OCT evaluation of RA was performed in 51 consecutive patients, undergoing TRI by long (25-cm) HRS. FD-OCT was performed from RA ostium to the puncture site. Acute damages such as intimal tears and medial dissections together with chronic intimal modifications, assessed as intimal hyperplasia indexes, were observed and compared between proximal and distal RA segments. Intimal tears were detected in 37% of patients, especially located in proximal RA segment (p = 0.09). Medial dissections were imaged in 9.8% of patients with no significant difference between proximal and distal RA segments. Intimal hyperplasia indexes were higher in distal RA segment, with no significant association with a previous history of TRI. In the setting of TRI, performed by long HRS, intimal tears represented the main RA injury occurring in about one-third of patients, while medial dissections only occurred in a small proportion of patients. Distal RA segment was more prone to intimal thickening, although this phenomenon was not associated with repeated transradial procedures.